Alarm lock



June 23, 1942. J. R. RODTH 2,287,572

ALARM LOCK Filed Feb. '17, 1940 5 Sheets-Sheet l r llllllldlllllll/fl /45 75 75 70 Y s @7052? f/700/1/ W all ATTORNEY} June 23, 1942. .1. R. RODTH 2,287,572

ALARM LOCK Filed Feb. 1'7, 1940 5 Sheets-Sheet 2 INVENTOR N v 'kfa'sizw/fitba rfl' ATTORNEY) June 23, 1942. J, RODTH 2,287,572

ALARM LOCK Filed Feb. 17, 1940 5 Sheets-5heet 3 ATTORN EYf" J. R. RODTH June 23, 1942.

ALARM LOCK Filed Feb. 17, 1940 5 Sheets-Sheet 4 v w m M m u 0 i E i m m T A INVENTOR .ffiSf/Qf/ BY VII/l June 23, 1942. J. R. RODTH 2,287,572

INVENTOR 6 $55 6 5 fanny W w ATTORN Patented June 23, 194-2 ALARM LOCK Joseph R. Ro'dth, Wilkes-Barre, P2... assigner to Eurgroth Alarm Corporation Application February 17, 1940, Serial No. 319,447

5 Claims.

The present invention relates to alarm locks, and more particularly to an improved construction of locking mechanisms including means for giving an. audible signal if the lock is forced or opened from the outside by any means other than its proper key, and from the inside by any means other than itsoperating knob.

One object of the invention is to provide certain structural improvements in the alarm lock of my Patent No. 2,170,521,,and at the same time toprovide for the accomplishment of the desired results by relatively simple mechanism.

Another object is to provide means for giving an audible signal which becomes operable upon a predetermined rise of temperature.

One of the distinctive features of my prior patent is the provision of a certain switch opener carried by the bolt, and movable within the bolt itself to switch opening position. In the present invention the switch opening means has been 5 improved, and although it is associated with the bolt, no movable parts are Within the bolt itself.

It will be understood that in addition to these specific objects and features, the mechanism of the present invention is intended to accomplish the more general objects of providing alarm lock means inaccessible to tampering and capable of being readily installed by others than skilled workmen without alterations in the door structure itself or adjacent structure.

Further objects and advantages will appear from the following description taken in connection with the accompanying drawings illustrating a preferred embodiment of the invention and in which:

Fig. 1 is a front elevation showing the lock housing and strike applied in cooperating relationship to a door and door jamb;

Fig. 2 is a vertical transverse section through the lock housing of Fig. 1, taken on the line 22 thereof and on an enlarged scale;

Fig. 3 is a horizontal sectional View through the lock housing, taken on the line 3'3 of Fig. 2;

Fig. 4 is a vertical longitudinal. sectional view through the lock housing;

Fig. 5 is a horizontal sectional view taken on line 55 of Fig. l; 7

Fig. 6 is a vertical transverse sectional view through the upper portion of the lock housing;

Fig. '7 is a circuit diagram;

Fig. 8 is a vertical sectional view of the bolt portion of the lock housing, viewed from the rear or door side thereof, taken on line 38 of Fig. 2'7 and showing the bolt in unlocked position;

Fig. 9 is a similar section as seen from the opposite side and taken on line 9-9 of Fig. 27;

Fig. 10 is a fragmentary vertical sectional view taken on line lfll0 of Fig. 9;

Figs. 11 to 13 inclusive are perspective views each showing an individual member of the slide assembly with its associated parts;

Figs. 1.4 and 15 are perspective detail views;

Fig. 16 is a vertical longitudinal sectional view showing the inside of the cover plate and the cam member thereon;

Fig. 17 is a similar view of the same parts showing them in a different position;

Figs. 18 to 21 are horizontal sections showing parts of the slide assembly in diffenet positions;

Figs. 22 to 24 are similar views showing associated parts in different positions;

Fig. 25 is an interior view of the top of the lock housing;

Fig. 26 is a vertical transverse sectional detail View showing certain parts within the housing above the battery;

Fig. 27 is a horizontal sectional view through the bolt portion of the lock housing.

Referring in detail to the drawings, the lock housing I is formed with an opening at its back, this opening being closed by a cover plate l4 next to a door surface I when the lock is in place, and in its front is an opening closed by a small housing door 2. At the lower part of the front of the housing are openings 3 behind which a bell. 4 is mounted. The housing I is secured to the door i by suitable screws. Into the housing i there is fitted a locking knob 5 to operate a bolt 6 independently of the key operation of a lock cylinder in the door. Opposite and operable independently of the knob 5 is any ordinary standary cylinder lock 1 which is attached separately to the door I. The bolt 6 is spring moved to locked and unlocked positions through a compression arm 15 which is loosely pivoted to the bolt by a pin 3 which is also the pivot for a rocking actuating arm 9, whose free end is provided with a circular opening into which fits a pin it (Fig. 27) fixed eccentrically on the knob arm H, the arm 9 having an extended portion 9 beyond the pin H) for engagement with a pin 12 on the cam ring l3, which is rotatably mounted on the inside of the back cover plate is and is moved by the cylinder lock 1 by means of the connecting rod It. The pin it! is moved clockwise, as viewed in Fig. 4, to the dotted line position during unlocking movement of the bolt 6, the parts then being in the positions shown in Fig. 9. The extended portion 9 of arm 9 moves in a generally rectangular slot I! (Figure 9) in the free end of the compression arm I5, the rotary motion of extended portion 9' giving to the compression arm I5 a rectilinear bolt moving motion to locked or unlocked position. The pin 8, which pivots compression arm I5 and actuating arm 9 to bolt 6, passes loosely through a slot I8 in the bolt 6. When the bolt 6 is withdrawn into the housing I, as shown in Figs. 8 and 9, the pin 8 is pushed to one extreme end of the slot I8 by a spring I9 (Fig. 8) carried by compression arm I5 and bearing on an inner bolt head shoulder at one end, its intermediate portion being looped around the pin 8 on compression arm I5, and its other end bearing against a pin fixed to the arm 9. As the spring I9 expands, one end of it forces the bolt 6 forward (Fig. 8) and the arm 9, which is pivoted on the pin 8, is forced downward by the other end until it bears on a lug 22. The lug 22 is stationary, being fixed to the front of the housing I and projecting inwardly of and horizontally across the housing. Its free end is tapped to receive a fastening screw 23 by which the back cover plate I4 is secured to the housing I. When the knob pin II! is moved clockwise, as viewed in Fig. 8, the arm 9 moves upward to its highest point and down again and the spring I9, during locking movement of the bolt 6, pushes the bolt into the strike 24, secured by screws to the door jamb, until it meets set screw 25 within the strike, as shown in Figs. 4 and 27. The set screw 25 causes the bolt to stop before the complete movement of the arm 9 has been effected, but as the arm is brought forward to its limit by the knob pin I8, it causes pivot pin 8 to move forward in the slot I8, thus further contracting the spring I9 and holding the bolt against screw 25 under pressure of this spring.

This spring pressure thus urges the bolt outwardly of the housing, but such movement is normally prevented by set screw 25 within the strike. As long as further movement of the bolt is thus prevented, the alarm will not sound, but if such movement occurs, as it would, for example, as a result of forcing the door open, or on forcing the parts to any position destroying this spring-urged abutting relationship of the bolt to the set screw, except key or knob return of the parts to unlocked position, the pressure of spring I8 on the bolt head shoulder will force the bolt outwardly of the housing to the extent permitted by the length of slot I8. This relatively slight outward bolt movement brings a lug 29, fixed on the top of the bolt shank, into actuating engagement with the trigger 3B of an alarm actuating slide and causes the alarm to sound as hereinafter more fully described. The inventions, moreover, provides means preventing silencing of the alarm even though inwardly directed pressure be exerted on the bolt head from outside the housing after the alarm has been set off.

When the bolt is actuated by the lock cylinder, the cam ring I3, which is rotatably mounted on the inside of cover plate I4, is rocked by means of the connecting rod I6 of the lock cylinder. The pin I2, Fig. 9, moves over the pin Ii! in the knob cam II, and during locking movement by the lock cylinder, pin I2 engages the lug 9 of arm 9, and rocks it, and hence the bolt 6, into locked position, the pin I0 being moved with arm 9 and so rocking knob 5 during this movement. When the bolt in its forward movement by pin I2 meets the set screw 25, the knob I I and its pin It, as shown in Fig. 4, have not quite moved to their extreme downward position of Fig. 4, which is below the knob axis. This condition is caused by the fact that, although the left end of spring I9. as viewed in Fig. 8, is urging arm 9, and hence knob pin I6, downwardly, the right hand end of spring i9 is urging compression arm I5 to the left, so that it presses toward the left against extension 9. To relieve this pressure, and permit arm 9, pin It] and knob cam II to reach the final position of Fig. 4, a cam 3i is formed on compression arm I5 over the rectangular slot in its free end, and during the final locking motion by the lock cylinder actuated pin I2, pin I2 momentarily bears on this cam and forces compression arm I5 to the left, as viewed in Fig. 4, against spring I9, moving the compression arm and its pivot pin 8 to the left far enough to relieve this pressure and allow the left end of spring I 9, as viewed in Fig. 8, to force arm 9 and thus pin in and knob cam II down to their lowermost position, shown in Fig. 4. By this time pin I2 has passed off cam 3i so that cam 3| and compression arm I5 occupy their positions shown in Fig. 4, in which arm 9 is stopped by lug 22 as above described. When the bolt is moved to unlocked position by the key and lock cylinder, the foregoing motions are reversed, the bolt being returned by pin I2 acting on a cam 32 formed on compression arm I5 opposite cam SI. Pin I2 thus works in the passage between these two cams. By engaging the extension 9 of actuating arm 9, the pin I2 exerts a lifting action on arm 9, but because the extension is approximately semi-circular and is open at the bottom (see Fig. 2) the pin I2 has no lowering action on arm 9, this being accomplished by the left hand arm of spring I9 (Fig. 8). In this way pin I2 is free to rotate through 360 as required by present day standary lock cylinders, even though the knob 5 and pin Ill rock through only some 220 in the present construction.

The invention provides means for causing the alarm to be set off when the door is pried, when the knob is operated by unauthorized means or when there are dangerously high temperatures on the premises. The alarm is preferably an electric bell and the lock mechanism itself forms part of the alarm or bell circuit. As in the drawings, within the housing I is an electric bell 4 of a standard commercial construction. It is attached to the housing by means of a cross bar 31 (Fig. 4) which is secured to the housing I by two screws 38, the current being derived from the dry cell batteries 39 and 40, which are secured in a frame of insulating material 4|, located within the upper part of the'lock housing I. They cannot be reached except through the small door 2, which can be opened only by means of the cylinder key, as more fully described hereinafter.

As shown in Fig. 4, the negative terminal 43 of the dry cell battery 48 is attached to the wire 45 (see also Fig. '7), which is connected to one terminal of the magnet coil 44 of the bell 4. The positive terminal of the battery 46 touches the contact spring 41, which is secured to the insulated frame M, and is connected with a wire 48 to the contact spring 49 which engages the negative terminal of the battery 33. The positive terminal of the said battery touches the contact spring 50, attached to the frame III by means of the rivet 5i which conducts the current to a terminal 52. The terminal 52 is entirely insulated from the housing I. The terminal 52 projects into cooperating relation with certain tumblers 54 and 55 (Fig. 4) and the alarm circuit is closed when either tumbler 54 and 55 touches the terminal 52, as shown in Figs. and 21, the current being carried through these tumblers to their respective springs 56 and 51, which bear against the wall of the metal housing I. The

current thus passes through the housing I, the

screws 38, the bar 31 to the vibrator of the bell 4, and soon to close the bell circuit as hereinafter more specifically described.

The mechanism which opens and closes the electric circuit is so arranged that once the alarm is set ofi it can be stopped only with the key, and to effect this the construction is as follows. The frame 4| which holds the batteries 39 and 40 has mounted on it a plate 60, which is held to the frame 4| (insulation) by two rivets BI and 62 (Fig. 23). This plate is the master plate to which several moving tumblers or triggers are attached, the terminal 52 passing through the opening 53 (Fig. 23) in the master plate 6D without contacting it. Attached to the plate GI] by means of a pin 64 is a sliding trigger 55 (Figs. 11, 23), which is provided with a guide slot 68, and the trigger spring 61. The trigger pin 35 of trigger 65 extends through the master plate 60, through the opening 68 therein, a second trigger pin 69 on trigger 65 extending through another opening II in the master plate Bil. The trigger spring 61 bears against the part of the insulating frame 4!, and urges the trigger 65 to the right, as viewed in Fig. 11, from which position it can be moved to the left the short distance permitted by slots 93 and 94 against pressure of the spring 61, being returned by the spring to the position of Figs. 11, 23 and 24.

The master plate 60 is longitudinally slotted at I4 to receive a tumbler release pin I5 which is slidable along a bar I6 fixedly mounted in a pair of lugs 71 and I8 turned up on the master plate. A coil spring I9 under compression surrounds the bar I6 and bears at one end against lug l8 and at the other end against the tumbler release pin l5, thus urging it constantly to the left as viewed in Fig. 11 and Figs. 18 to 24.

The master plate IEO also has mounted on it a manually operated rocking release arm 80, which is pivoted on plate 6!) by a pin BI, and has a release finger 82 bent at a right angle and pro jecting through a release finger opening 83 in the master plate. The release arm 8!) is slotted at 84 to receive the actuating pin 85 of a push button 85 mounted slidably in the casing I (Fig. 24) and projecting therebeyond to be accessible for manual operation. A spring 81 is fixed to the release arm 85) and bears against an adjacent portion of the insulating frame, thereby constantly urging release arm 83 and push button 86 toward the right as viewed in Fig. 24 and towards the outer push button position of Fig. 21.

Cooperating with the release finger 82 is a first circuit closing tumbler 54 (Fig. 12) pivotally mounted on the master plate 5!! by a pin 9I (Fig. 22). The tumbler 54 is provided with openings 92, 83, and 94 to receive the trigger pin 35, release finger 82 and the terminal 52, respectively. Its free end is formed with a holding hook 95 cooperable with the release finger 82 (Figs. 21 and 22). The circuit closing tumbler 54 is always urged upwardly towards its position in Fig. 22 by its spring 56 bearing on the wall of casing I.

In Fig. 22' the push button 86 is in inner position and the release finger 82 isurged against the edge of hook on the free end of tumbler 54 without holding it down against its spring 55, the spring 56 holding the tumbler up with its upper edge contacting the tumbler holding pin I06 of a slide I (15 (Fig. 13) hereinafter referred to, on the top edge of the tumbler 54 above its hook.

Depression of tumbler 54 lowers its hook 95 far enough to permit release finger 82 to move over the hook under the action of spring 81, and thereby hold the hook and tumbler 54 down in the position shown in Fig. 21, with the tumbler 54 out of contact with terminal 52.

Referring to Fig. 21, it will be seen that with the push button out, hooked tumbler 54 is held down free and clear of all trigger pins and terminal 52, and remains so as long as push button 86 is in its outer position with the release arm finger 82 holding down the tumbler by its hook 95. When the push button 86 is in its inner position, the release arm finger 82 is in the position of Fig. 18, 19 or 22, in which it no longer holds down the hook and tumbler 54, the tumbler, in these positions of the parts, bearing with its shoulder 96 upon the pin 15 in Fig. 19, or with its hooked end on pin I06 as in Fig. 18, or with the edge of its opening 94 on terminal 52 as in Fig. 20;

The slide I65 is moved to the position of Fig. 18 when, and only when, the bolt is key actuated to unlocked position. But upon every actuation of the bolt from locked to unlocked position, whether its movement is caused by key or knob, pin 15 is moved to the right, as hereinafter described, away from or off shoulder 95, against its coil spring pressure, which thereafter causes it to snap back to the position of Fig. 18 before the unlocking movement is quite completed. This riding off shoulder 96 by pin 15, when only pin i5 is holding down tumbler 54, permits tumbler 54 to move up and contact terminal 52 on knob return of the bolt to unlocked position. On key return of the bolt to unlocked position, pin I05 rides, as shown in 18, upon the upper edge of the hooked end of tumbler 54 before pin 15 leaves shoulder 95, thus moving the tumbler 54 down and holding it free of terminal 52. Before completion of the unlocking movement, pin 15 is spring returned to its position above shoulder 95, so that when slide I05 and its guide pin I05 move to the left during key locking movement of the bolt, tumbler 54 will be held down free of terminal 52 by the pin l5 even though pin I5 5 has moved away, as later described.

A second circuit closing tumbler 55 (Fig. 13) functions to close the bell circuit and cause sounding of the alarm when the door is pried or forced open, whether by a tool or by any other means. The tumbler is rockably mounted on the pin SI and is positioned adjacent and parallel to the tumbler 5-4 (Figs. 18 and 24). The spring 51, similar to the spring 55, has one end fast the tumbler 55 and it other end free, but compressed and bearing on the adjacent wall of easing I, to urge the tumbler 55 constantly upwardly about pivot pin 9I. The trigger finger 841 of trigger slide 65 on master plate 50 extends through the opening 98 of tumbler 55, and the other trigger finger 59 of said trigger slide extends into the opening H98 in tumbler 55, the finger 59, in its right hand position of Fig. 18, bearing on a shoulder Iiii of the edge defining the tumbler opening I85. Into a third opening I02 in said tumbler extends the terminal 52, normally without touching the tumbler. A clearance opening I04 is provided in the tumbler 55 in which travels the tumbler release pin I5 of master plate 55, above tumbler 54.

When the right hand trigger finger 59 of trigger slide 55 on the master plate, on which normally bears shoulder IBI of opening I in tumbler 55, is in the position of Fig. 18, the lower edge of opening I02 in tumbler 55 does not touch the terminal 52. When the trigger finger 30 -1noves to the left as viewed in Fig. 18, it rides beyond the shoulder IfiI and over the lowermost part of the opening I50 (as viewed in Fig. 18), whereupon spring moves tumbler 55 upward- 1y, bringing the lower edge of its opening I02 into contact with the terminal 52, thereby closing the alarm bell circuit and causing the alarm to sound.

Slidably mounted on the second tumbler 55 (Fig. 13) is the key cam plate slide H35, having the pin I05 at one end traveling in a guide slot III in tumbler 55, and at its other end having a guide extension I I2 whose narrow neck I i3 passes though a second guide slot H4 in said tumbler. The cam plate slide is moved on tumbler 55 by lugs on the key actuated cam ring i3, which is rotatably mounted on the inside of the cover plate I4, and for this purpose the slide 25 is provided with a pair of spaced and oppositely bent ears I l5 and M1, by means of which the side $05 is moved to left or right by the lugs H8 and H5 formed on the cam ring I3. On locking movement by the key, while the cam ring pin I2 is riding between the cams 3i and 32 of compression arm I5, and is thereby moving the bolt to locked position, cam ring lug II8 contacts ear H6 (Fig. 16) and moves slide I05 to the left along tumbler 55. (See also Figs. 18 and 19). As the cam ring I3 and its pin I2 rotate through 360, the other lug Ii9 will, during cam ring rotation, meet ear Ill and ride up and over itsbent surface, pressing the ear II! and hence slide I05 and tumbler 55 downwardly about pivot 0| (as viewed in Fig. 19), the lug II9 then riding off ear IE1 into the space between ears H6 and H1, releasing tumbler 55, which is then moved to its former upper position by its spring, the lug II9 then continuing its rotary motion for the remainder of its 360 movement without causing any action on any part.

On reverse rotation of the cam ring I3, by key movement of the bolt to unlocked position, lug II9 rides into the'space between ears H5 and III, then contacts ear II"! and moves it and thus slide I55 back to its former position (Fig. 16). Lug II9 rides upon and over ear H5, depressing it and slide I55, then into and arcuately out of the space between these ears. This depression of slide I55 and its tumbler 55 depresses tumbler 54 by pin I05 until finger 82 engages hook 95 and tumbler 54 is re-latched in inoperative, or un-set, position.

Referring to Fig. 4, it will now be seen that if the normal locking relation between bolt 5 and set screw 25 has not been destroyed, and tumbler 54 is held down at its hook 55 by finger 82 (Fig. 21) the bolt may be returned to unlocked position by either key or knob without causing the alarm to sound, since finger 69 has never moved off shoulder IOI and tumbler 55 cannot rise and contact terminal 52.

If however, the normal locking relation between bolt 5 and set screw 25 has been destroyed in any manner permitting bolt 5 to move to the left beyond its position in Fig. 4, lug 29 will thereby have moved finger 30 to the left, and thus moved finger 50 off shoulder IOI of tumbler 55, upon which this tumbler will move up, contact terminal 52 and so cause sounding of the alarm.

If the alarm has been caused to sound in this manner, inwardly directed pressure on bolt 5 will not silence it, since such pressure cannot have the effect of 10Wellllg tumbler 55, but only push finger 69 against the edge of opening I00 below the shoulder (Fig. 21). Nor will knob actuation of the bolt in any direction silence the alarm, because knob actuation of the bolt never depresses tumbler 55. Only key unlocking movement of the bolt will silence the alarm, by moving lug 29 away from finger 30 as a result of inward bolt movement, and depressing slide I05 to bring shoulder ml of slide 55 lower than finger 59, whereupon spring 61 pushes the finger over the shoulder and so holds tumbler 55 down and out of contact with terminal 52, thus restoring tumbler 55 to the same circuit breaking position it occupied in normal door locked relation of bolt 6 to set screw 25, before lug 29 moved finger 30 to bring finger 69 off shoulder IOI.

By setting the push button in, and then looking the door from the outside by key movement of the bolt to its locking position against set screw 25, the alarm will be caused to sound if the bolt is knob actuated to unlocked position. Thus, even if an opening is made in the door and the knob thereby reached from the outside and actuated to unlock the door, the alarm will be sounded. After such push button depression and subsequent locking of the door by the key, the bolt can be moved to unlocked position without setting off the alarm only by key operation.

Fig. 9 shows the position of the parts before such setting and locking. When button 86 is pushed in from its position in Fig. 21 to its position in Fig. 18, tumbler 54 i no longer held down by release arm finger 82, and consequently moves upwardly, by spring 55, until its upper edge above its hook rests against the head of guide pin I05 on slide I55. If the door is now closed and the bolt 6 brought to locking position against set screw 25 by means of the key, slide I05 will thereby be moved by lug HR to the position of Fig. 19, as already described. This moves pin I06 oif slide 54, so that its upper edge shoulder 90 bears against tumbler release pin I5, and further upward movement of tumbler 54 is prevented only by this pin, which, in the position of Fig. 19 prevents the lower edge of tumbler opening 94 from contacting terminal 52.

Upon any unlocking movement of the bolt, whether by key or by knob, pin I5 is moved to the right a distance sufficient to bring it off shoulder 95. For this purpose (Figs. 4 and 9) a small bell crank lever I23 is pivoted at I24 on bolt 6, and has its lower arm I25 engageable with fastening screw lug 22, and its upper arm I30 engageable with pin I5. A spring I28 is coiled about the pivot I24 and has one end bearing on a fixed pin I29 on the bolt and its other end engaging a flange I3! on the upper bell crank arm I30, the tension of the spring being exerted in a direction to cause the bell crank lever t b urged constantly counterclockwise into the position of Fig. 4. During any locking movement of the bolt, arm I30 is dragged idly past pin I5,

- once past it snapping into the position of Fig. 4.

On return motion of the bolt to unlocked position, whether by knob or by key, arm I30 engages p1n I5 and pushes it to the right against the pressure of its coil spring I9 until lower bell crank arm I meets fastening screw lug 22, whereupon the remainder of the unlocking movement of the bolt causes the bell crank lever I23 to rock clockwise enough to move it upper arm I away from pin 15, thus releasing the pin and allowing it to be returned to the left by its spring. In the completed unlocked position of the bolt, bell crank lever I23 occupies the position of Fig. 9, held there by lug 22. The first part of bolt unlocking movement carries lower arm I25 away from lug 22 and the bell crank lever is then free to be spring moved counterclockwise to its upper position, with its upper arm I30 in engageable relation to pin 15.

It will now be seen that, although pin 75 is moved off shoulder 96 by any unlocking movement of the bolt, yet if the bolt is unlocked by the key, slide I will thereby be moved to the position of Fig. 18, so that slide pin I56 rides on and holds down tumbler 54 before bell crank arm I30 reaches 1 in I5 and pushes it olf shoulder 55. Thus, on key movement of the bolt to unlocked position, tumbler 54 cannot move up to contact terminal 52 and sound the alarm. If, however, he bolt is moved to unlocked position by the knob instead of by the key, slide I55 will not be moved to the right or at all, since there will be no movement of lugs H3 and IIS, and the slide guide pin I86 will remain to the left, as in Fig. 19, and since tumbler 54 is now held down only by pin I5, the moment pin I5 is moved 01f shoulder 95 by the upper bell crank arm I33, slide 54 moves upwardly by its spring 55, the lower edge of its opening 94 contacts terminal 52, thereby completing the alarm circuit and causing the alarm to sound.

If it is not desired to have the alarm sounded in thi manner by knob operation after key locking, the push button 85 is simply not depressed, so that tumbler 54 is held down by finger 82 on tumbler hook 95 and the tumbler 54 cannot rise to sound the alarm whatever the movements of pins I86 and I5 until the push button is depressed and the hook released.

If the alarm has been set off by knob operation after key locking as above described, the key must be used to shut off the alarm. To shut off the alarm in such case, the door is closed and locked by the key, which moves slide I35 to the right, depresses pin I66 and thereby relatches slide 54 under finger 82, thus stopping the alarm.

The foregoing setting of the mechanism to cause knob unlocking to sound the alarm does not affect the means already described for causing the alarm to sound by any outward movement of the bolt 3 beyond that determined by the set screw 25.

The reason for closing the door is merely to make use of set screw 25 to prevent the bolt from moving so far out of its casing that finger B9 is pushed off shoulder IIlI on tumbler 55 by engagement of bolt lug 29 with finger 30, since that would allow tumbler 55 to rise and thereby itself cause sounding of the alarm.

It will be understood that the lugs I 58 and I I9, and pin I2 on key operated cam ring I3 are so located on the ring with respect to the comiecting rod IIi that although the key may have to be given some additional rotary motion to withdraw it after the cam ring lugs and pin have completed moving their cooperating parts, such additional movement of the key is an idle one so far as those parts are concerned. Since there is only one pin I2 on the cam ring, and the lugs H8 and H9 are apart, the ring may be rotated enough idly to permit key withdrawal-without performing any of its mechanism actuating functions.

Referring now in more detail to the battery door 2 provided in the upper front of the casing I, (Figs. 1, 3) a projection I4I on one side of the door fits within and behind the casing front I42, and on the other side the door is provided with a pair of lugs or projections I43, each fitting within the casing behind one of a pair of similarly spaced keeper flanges I44 on a manually operable lock I45 (Fig. 6) The lock slide is movable along the right hand side wall of casing I as viewed in Fig. 4, in which its upper part is covered by the exposed portion of insulation battery casing 45, this upper part (Fig. 6) having a slide shifting button I48 projecting through a short slot I43 in the casing side wall. Manual downward movement of lock slide I45 by its shift button I43 (Figs. 4, 6), that is, away from the observer as viewed in Fig. 3, will move the locking or keeper flanges I44 downwardly beyond the door lugs I43, thus freeing the door lugs and permitting the door 2 to be completely removed from the casing.

Key controlled means are provided to prevent such door unlocking movement of the lock slide I45, unless the key is inserted in the cylinder I and cam ring I3 is turned by it. Referring to Fig. 4, this means includes a bell crank lever I52 pivoted at I53 to part of the casing I and having a spring I54 urging its locking arm I55 into the position of Fig. 4 and its actuating arm I56 into the path of lugs II8 and I I9 of cam ring I3. The free end of the spring I54 bears against the upper surface of a partition I51 extending from side to side of the casing I above the alarm hell 4. When the slide shift button I43 is in its upper position lever arm I55 blocks the slide I45 against downward or unlocking movement unless the key to cylinder I is inserted therein and cam ring I3 thereby turned to rock lever arm I downwardly, that is, counterclockwise as viewed in Fig. 4, which movement rocks locking arm I55 to the left and clears the path for the battery door locking slide to be moved downwardly to battery door unlocking position by manual downward pressure on slide shifting button I48. Upon key removal and manual movement of button I48 to its upper position, arm I55 snaps under the bottomof lock slide I45, so that, except by preliminary use of the key, the battery door cannot be opened.

The lugs H3 and H9 and lever actuating arm I56 are so arranged with respect to each other that actuating arm I 56 is neither rocked nor cantacted by either lug unless the cylinder key has been inserted and turned out of its inserting .position, which is its withdrawing position, in the cylinder. Thus the cylinder key is required not only to shut off the alarm, once it has started to sound, but also to open the battery door, so that the batteries are unreachable for manipulation except by the lock key itself.

The means provided by the invention for setting off the alarm upon dangerous rise in temperature is shown diagrammatically in Fig. 7, and includes a thermostatic spiral spring I65, whose tendency is to uncoil upon increase in temperature, so that its outer end IGI may contact the terminal 32 of a wire I53 connected as shown in Fig. '7 in the alarm circuit. The inner end of the thermostatic coil is permanently connected to the casing I ,the coil in cup I66 itself being secured to the inside top face of the casing as shown in tion for testing, for example.

Figs. 25 and 26. Upon a predetermined rise in temperature contact between the Wire terminal I62 and the outer end lfil of the coil closes the alarm circuit and causes the alarm to sound.

The mechanism may include the safety device, shown in Fig. 5, for preventing the bolt from being moved to its outermost or alarm sounding position when the door I has not been closed but which is optionally operable while the door is open to permit the bolt to move to alarm sounding posi- Referring to Fig. 5, a lug 15 formed on the inner side of casing l, carries an arm Hi to which is pivoted at 11 a small bell crank lever 18, constantly urged counterclockwise by a flat leaf spring 19. One arm 80 of this lever protrudes through a slot in the casing and when the door I has not been closed, the arm 80 and the other arm Bl of the bell crank lever, constituting the bolt stop, occupy the dotted line positions of Fig. 5. In this position arm 8| moves into the path of a lug 85 on the lower part of the bolt 6 andthereby prevents the bolt from moving from dotted line position to full line position, the full line position being the normal locked position of Fig. 4.

If the door has been closed, however, arm Bi) strikes keeper 24 causing stop arm 8| to be rocked clockwise to the full line position of Fig. where it is free and clear of the path of travel of bolt lug 85. Thus, when the door has once been closed and locked. no tampering with this bell crank lever will have any effect on the alarm mechanism or its operation. It will be evident that if the door I has not been closed, the bell crank lever may be manually moved to the full line position of Fig. 5 for the purpose of testing the alarm. On being manually released, it will return to dotted line position of Fig. 5 in which it does not interfere with unlocking movement of the bolt, but once unlocking bolt movement has occurred, the bell crank lever will prevent bolt locking movement unless it is rocked clockwise either manually when door I is open, or by contacting keeper 24 when door I has been closed.

What is claimed is:

1. An alarm lock mechanism including a lock casing, key actuated cylinder lock, bolt, keeper, bolt shifting knob, circuit controlled audible alarm, an electric circuit therefor including asource of current, a bolt controlled circuit closer in said circuit, knob actuated means for moving said bolt, key actuated means for moving said bolt and said knob actuated means, bolt abutment stop means within the keeper for limiting bolt movement outwardly of the casing to normal locking position within the keeper, and spring means associated with the bolt within the casing and urging said bolt further outwardly of the casing, and bolt actuated means in the casing operable by such further bolt movement outwardly of the casing for bringing said circuit closer into circuit closing alarm sounding position.

2. An alarm lock mechanism including a lock casing, key actuated cylinder lock, bolt, keeper, bolt shifting knob, circuit controlled audible alarm, an electric circuit therefor including a source of current, a bolt controlled first circuit closer'in said circuit, knob actuated means for moving said bolt, key actuated means for moving said bolt and said knob actuated means, bolt abutment stop means within the keeper for limiting bolt movement outwardly of the casing to normal locking position within the keeper, and

"spring means associated with the bolt within the casing and urging said bolt further outwardly of the casing, bolt actuated means in the casing operable by such further bolt movement outwardly of the casing for bringing said circuit closer into circuit closing alarm sounding position, a second circuit closer in said circuit and constantly urged toward circuit closing position, manually controlled setting means for bringing said second circuit closer from inoperative position into preparatory circuit closing position, knob released holding means for holding said second circuit closer out of circuit closing position, means actuated by knob unlocking bolt movement for moving said holding means out of holding position, said second circuit closer being thereupon movable to circuit closing, alarm sounding position, and key controlled means for returning said second circuit closer to inoperative position.

3. An alarm lock mechanism including a lock casing, key actuated cylinder lock, bolt, keeper, bolt shifting knob, circuit controlled audible alarm, an electric circuit therefor, a bolt controlled circuit closer in said circuit including a source of current, knob actuated means for moving said bolt key actuated means for moving said bolt and said knob actuated means, bolt abutment stop means within the keeper for limiting bolt movement outwardly of the casing to normal locking position within the keeper, and spring means associated with the bolt within the casing and urging said bolt further outwardly of the casing, bolt actuated means in the casing operable by such further bolt movement outwardly of the casing for bringing said circuit closer into circuit closing alarm sounding position, a circuit current source within said oasing, a casing door giving access to said current source, and a look within said casing for said door and moved by said key actuated means into door unlocking position.

4. 'An alarm lock mechanism including a lock casing, a key actuated cylinder look, a bolt, a cooperating keeper, a bolt shifting knob, a circuit controlled audible alarm, an electric circut therefor, including a source of current, having a circuit closing terminal contactor, a bolt controlled spring pressed circuit closing tumbler urged constantly toward circuit closing contact with said terminal contactor, a holding device bearing on said tumbler and normally preventing such contact, a bolt actuating arm, a bolt spring yieldingly connecting said arm with said bolt and urging said bolt in an outward direction with respect to said casing, knob controlled means for rocking said bolt actuating arm and thereby said bolt into locking and unlocking positions, cylinder lock controlled means for rocking said bolt actuating arm and said knob controlled means into locking and unlocking positions, bolt abutment stop means within the keeper for limiting bolt movement outwardly of the casing to normal locking position within the keeper against the pressure of said bolt spring, and means movable with additional bolt movement beyond normal locking position for releasing said holding means from said tumbler and thereby freeing it for circuit closing, alarm actuating contact with said terminal contactor.

5. An alarm lock mechanism including a lock casing, a key actuated cylinder lock, a bolt, a cooperating keeper, a bolt shifting knob, a circuit controlled audible alarm having a circuit closing terminal contactor, a first bolt controlled spring pressed circuit closing tumbler urged constantly toward circuit closing contact with said terminal contactor, a holding device bearing on said tumbler and normally preventing such contact, a bolt actuating arm, a bolt spring yieldingly connecting said arm with said bolt and urging said bolt in an outward direction with respect to said casing, knob controlled means for rocking said bolt actuating arm and thereby said bolt into locking and unlocking positions, cylinder lock controlled means for rocking said bolt actuating arm and thereby said bolt and said knob controlled means into locking and unlocking positions, bolt abutment stop means within the keeper for limiting bolt movement outwardly of the casing to normal locking position within the keeper against the pressure of said bolt spring, means movable with additional bolt movement beyond normal locking position for releasing said holding means from said tumbler and thereby freeing said tumbler for circuit closing, alarm actuating contact with said terminal contactor, a second bolt controlled spring pressed circuit closing tumbler urged constantly toward circuit closing contact with said terminal contactor, manually operable locking means for maintaining said second circuit closing tumbler in inoperative position and releasing it therefrom into preparatory circuit closing position, tumbier holding means bearing on said second tumbler for preventing its movement from preparatory position to circuit closing position, bolt controlled means for removing said holding means from said tumbler and freeing it for circuit closing alarm sounding movement, tumbler return means for restoring said second tumbler to inoperative position in held relation to said manually operable locking means, and a cylinder lock controlled actuator associated with said tumbler return means for moving it to tumbler returning position by cylinder lock movement of said bolt to unlocked position and in advance of the freeing of said tumbler by said tumbler holding means.

JOSEPH R. RODTH. 

